Kabul before the attacks, as seen by the Ikonos satellitePicture by Space Imaging Inc

By BBC News Online science editor Dr David Whitehouse

The US Government has bought all rights to all the pictures of Afghanistan and surrounding areas taken by the privately operated Ikonos high-resolution imaging satellite.

The US National Imagery and Mapping Agency (Nima) has "assured access to imagery in support of Operation Enduring Freedom", the name for the military campaign against terrorist and military targets in Afghanistan.

Under the terms of the contract, Space Imaging, the company that operates Ikonos, will not "sell, distribute, share or provide the imagery to any other entity".

Although Ikonos images can be sold commercially, the US Government has the right to impose such restrictions, which are known as "shutter control".

Exclusive rights

The objective is for the US Government to obtain an additional pair of eyes over Afghanistan to supplement its own spy satellites and, more importantly, to deny others the use of the images.

Space Imaging's two-year-old Ikonos satellite provides black-and-white images capable of seeing objects one metre (3.2 feet) across. It also takes colour pictures with 4-m (13.1-ft) resolution. The detail in the Ikonos images already taken show a line of trainees from the al-Qaeda network marching between camps in Jalalabad.

Under American law, the US Defense Department has legal powers to exercise shutter control over civilian satellites launched from the US to prevent enemies using the images while America is at war.

According to reports, the decision to shut down access to satellite images was taken last week, after reports of heavy civilian casualties near Jalalabad.

Damaging scoops

However, the move by the Pentagon simply to resort to buying exclusive rights to all the Ikonos pictures could be something of a canny move.

Had it just used its legal powers of shutter control instead, the Pentagon might have been confronted by media companies - seeking potentially damaging scoops in the pictures - filing lawsuits under the Freedom of Information Act.

The US military does not need the Ikonos pictures because it has six imaging satellites already in orbit, augmented by a seventh launched a few days ago.

Four of the satellites are called Keyholes and can see details as small as 10 centimetres (4 inches) across.